The present invention relates to self-flushing fluid apparatus. The invention is particularly useful in a pulsator device, such as described in my U.S. Pat. No. 4,781,217, and is therefore described below with respect to this application, but it will be appreciated that the invention could advantageously be used in many other applications.
Pulsator devices, such as described in the above-cited patent, include a housing having an inlet port formed with a restricted inlet orifice for receiving fluid in a continuous manner and at a relatively low rate, and an outlet port formed with a larger orifice controlled by an outlet valve which opens at a relatively high pressure and closes at a relatively low pressure. Thus, fluid may be continuously introduced at a low rate into the housing, thereby increasing the pressure within the housing until the outlet valve opens, at which time the outlet valve opens to discharge the fluid until the pressure within the housing drops to the predetermined low value, when the outlet valve recloses. Such pulsator devices are used, among other applications, in water irrigation systems to enable sprinklers and other irrigation devices to be fed with water continuously at a relatively low rate but to discharge the water periodically at a relatively high rate.